Effect of Sunscreen Application Under Maximal Use Conditions on Plasma Concentration of Sunscreen Active Ingredients

Abstract

IMPORTANCEThe US Food and Drug Administration (FDA) has provided guidance that sunscreen active ingredients with systemic absorption greater than 0.5 ng/mL or with safety concerns should undergo nonclinical toxicology assessment including systemic carcinogenicity and additional developmental and reproductive studies. OBJECTIVE To determine whether the active ingredients (avobenzone, oxybenzone, octocrylene, and ecamsule) of 4 commercially available sunscreens are absorbed into systemic circulation. DESIGN, SETTING, AND PARTICIPANTS Randomized clinical trial conducted at a phase 1 clinical pharmacology unit in the United States and enrolling 24 healthy volunteers. Enrollment started in July 2018 and ended in August 2018.INTERVENTIONS Participants were randomized to 1 of 4 sunscreens: spray 1 (n = 6 participants), spray 2 (n = 6), a lotion (n = 6), and a cream (n = 6). Two milligrams of sunscreen per 1 cm 2 was applied to 75% of body surface area 4 times per day for 4 days, and 30 blood samples were collected over 7 days from each participant. MAIN OUTCOMES AND MEASURESThe primary outcome was the maximum plasma concentration of avobenzone. Secondary outcomes were the maximum plasma concentrations of oxybenzone, octocrylene, and ecamsule. RESULTS Among 24 participants randomized (mean age, 35.5 [SD, 10.5] years; 12 [50%] women; 14 [58%] black or African American), 23 (96%) completed the trial. Systemic concentrations greater than 0.5 ng/mL were reached for all 4 products after 4 applications on day 1. The most common adverse event was rash (1 participant with each sunscreen).

Photoprotection of the future: challenges and opportunities

“…Specifically, after 75% body surface application at maximal usage conditions, organic filters were absorbed and had detectable plasma levels. 37 However, the clinical relevance of these findings is completely unknown. Further studies are needed to understand the impact of this information on the safety of organic filters.…”

“…Of note, a recently published study has reported the penetration of topically applied organic filters into the blood circulation of human subjects. Specifically, after 75% body surface application at maximal usage conditions, organic filters were absorbed and had detectable plasma levels . However, the clinical relevance of these findings is completely unknown.…”

Commentary on “‘Hypoallergenic’, ‘Sensitive Skin’, and ‘For Kids’: Has industry improved labelling standards when it comes to sunscreens?”

“…With the recent increased scrutiny from the FDA into all presently available chemical sunscreen filters used in the United States and the recent JAMA article on sunscreen absorption, it is imperative that dermatologists understand what chemical filters are associated with allergy, understand that absorption in compromised skin may be elevated and finally, understand that sunscreen labeling may not help consumers. No sunscreen with allergenic and irritating UV filters, fragrances, preservatives, emulsifiers, etc should hold the labels “sensitive skin” or “hypoallergenic.” It is my opinion that chemical filters should not be used in sunscreens labeled “baby.” It would prove helpful to both consumers and physicians if the FDA mandated strict guidelines for placeholder terms like “sensitive skin,” “hypoallergenic,” and “for kids” not only for sunscreens but for all skincare—in particular those marketed for babies and children.…”

“…It is beyond the scope of this editorial and the science is still evolving; however, I think it is important as dermatologists that we continue to review the current literature on this topic. 21 With the recent increased scrutiny from the FDA into all presently available chemical sunscreen filters used in the United States and the recent JAMA article on sunscreen absorption, 22 it is imperative that dermatologists understand what chemical filters are associated with allergy, understand that absorption in compromised skin may be elevated and finally, understand that sunscreen labeling may not help consumers. No sunscreen with allergenic and irritating UV filters, fragrances, preservatives, emulsifiers, etc should hold the labels "sensitive skin" or "hypoallergenic."…”

Modifiable risk factors in paediatric atopic dermatitis: is the sun finally shining?

“…However, would such an effect of UVR then work to protect against both the transient and persistent AD subtypes? And should sunscreen be advocated despite systemic absorption that might take place that exceeds regulatory limits following universal application?…”